#include <iostream>
using namespace std;

template <class ElemType> class A {
  private:
    ElemType a;

  public:
    A(ElemType x) : a(x) {}
    void Show() const { cout << a << endl; }
};

int main() {
    A<string> obj("Hello, world!");
    obj.Show();

    return 0;
}
